So I've begun pulling the carpet up to put down solid 3/4" oak flooring. I'd previously thought I needed to pull the particle board out and I'm trying to figure out if I still need to. I have now found out I have

1/2" plywood sub / layer of tar paper / 5/8" particle board.

I'm using 2" staples to fasten it down. Should I still tear out the particle board and replace with OSB?